Deciphering CAD: Structure and function of a mega-enzymatic pyrimidine factory in health and disease.
Francisco Del Caño-OchoaSantiago Ramón-MaiquesPublished in: Protein science : a publication of the Protein Society (2021)
CAD is a 1.5 MDa particle formed by hexameric association of a 250 kDa protein divided into different enzymatic domains, each catalyzing one of the initial reactions for de novo biosynthesis of pyrimidine nucleotides: glutaminase-dependent Carbamoyl phosphate synthetase, Aspartate transcarbamoylase, and Dihydroorotase. The pathway for de novo pyrimidine synthesis is essential for cell proliferation and is conserved in all living organisms, but the covalent linkage of the first enzymatic activities into a multienzymatic CAD particle is unique to animals. In other organisms, these enzymatic activities are encoded as monofunctional proteins for which there is abundant structural and biochemical information. However, the knowledge about CAD is scarce and fragmented. Understanding CAD requires not only to determine the three-dimensional structures and define the catalytic and regulatory mechanisms of the different enzymatic domains, but also to comprehend how these domains entangle and work in a coordinated and regulated manner. This review summarizes significant progress over the past 10 years toward the characterization of CAD's architecture, function, regulatory mechanisms, and cellular compartmentalization, as well as the recent finding of a new and rare neurometabolic disorder caused by defects in CAD activities.
Keyphrases
- coronary artery disease
- hydrogen peroxide
- transcription factor
- cell proliferation
- healthcare
- public health
- gene expression
- mental health
- dna methylation
- health information
- hepatitis c virus
- high resolution
- genome wide
- small molecule
- cell cycle
- human immunodeficiency virus
- amino acid
- risk assessment
- breast cancer cells
- signaling pathway
- hiv infected
- antiretroviral therapy
- human health